Coded identification of the agency controlling the syntax, and of the character repertoire used in an interchange.Notes:1. The data value consists of the letters 'UN', upper case, identifying the syntax controlling agency, directly followed by an a2 code identifying the character repertoire used.

UNOA

UN/ECE level A

As defined in the basic code table of ISO 646 with the exceptions of lower case letters, alternative graphic character allocations and national or application-oriented graphic character allocations.

UNOB

UN/ECE level B

As defined in the basic code table of ISO 646 with the exceptions of alternative graphic character allocations and national or application-oriented graphic character allocations.